Republican former Mayor Rudy Giuliani on Tuesday urged the GOP-run US Senate to confirm Loretta Lynch as attorney general.

Giuliani said he worked with Lynch during both her stints as US attorney in Brooklyn and found her ­impressive.

“During that time, she was a balanced professional and a dedicated public servant,” Giuilani wrote in a letter to Sen. Lindsey Graham (R-SC), one of four ­Republicans backing Lynch, hoping to bolster Graham’s stance.

“As a former senior official in the Justice Department, I can further attest that her skill set seems very appropriate to the tough tasks she would face as ­attorney general.”

Giuliani, who served as Manhattan US attorney, said that if it were up to him, he’d confirm Lynch despite a few ideological differences.

He said that under the Constitution, President Obama has the right to choose his Cabinet members, as long as they are qualified. Lynch, he said, fits the bill.

The Senate leadership has held up Lynch’s confirmation until an unrelated bill on human trafficking is taken up.

GOPers are also threatening to block Lynch because she backs Obama’s use of executive power to stop deportation of illegal immigrants.